Mandrel for bending machines



J. W. TAYLOR MANDREL FOR BENDING MACHINES Filed Sept. 23, 1921 2 Sheets-Sheet 1 J. W. TAYLOR MANDREL FOR BENDING-MACHINESY Filed Sept. 25, 1921 2 Sheets-Sheet 2 All ll atented Dec. 235, i924.

gTi lTlll MANDREL FGE EWING- .lpplication filed September 23, 1821.. Serial No. scares.

plates to approximate a bean of uniformstrength, the individual leaves are separately curved and tempered and later assembled. The leaves are usually received from the furnace in a highly heated condition and substantially straight, placed on a mandrel and bent to the proper radius of curvature, and then plunged into a cooling medium such as oil or water, while still held on the mandrel. It is essential in obtaining spring blades having proper and unizlorm properties that the quenching action be uniform, that is, that all parts of the spring leaf be simultaneously subjected to the cooling action of the liquid and that the liquid be free to flowover its surface throughout the quenching operation;

it has heretofore been attempted to secure by various devices the quiclr and uniform quenching desired by supporting the leaf so that the. quenching liquid canflow freely over its surfaces. For instance, grooves have been 'cut diagonally in the surface of the mandrel against which the leaf rests to allow a flow of cooling liquid between the leaf and mandrel, and in another form of prior device the mandrel or master plate has had longitudinal rods mounted thereon upon which the work is supported and holes have been formed in the plate to allow the quenching liquid to flow to the under side of the work, These and other previous devices of this character have, however, not proven entirely satisfactory in operation, the physical properties of the resulting spring leaf varying along its length due [to the fact that the liquid does not have free access to all surfaces of the work, and because oi the formation of gas pockets adjacent the work due to poor circulation, which causesoft spots in the metal and lit has also been realized that the leer I should be cooled at approximately the same rate on bothsides and in an eii'ort to obtain this uniio rate or balanced cooling action the areas of contact of the holding means on then posite sides of the plate have been made so otentially equal, so that the surface exposed to the cooling liquid is the same in area, on both sides. This increase in area of contact between the leaf and its supports further decreases the speed of quenching.

The object of the. present invention is to provide a mandrel constructed and designed to be used in the bending and quenching operation, whereby a spring leaf may be firmly held and unii orinly quenched, the cooling liquid being enabled to sweep over the plate ifreely on both sides, the liquid flowing edgewise of the plate, thereby enabling such liquid to cool the full cross section of the metal the same rate.

The invention may be embodied in va rious forms, several of which, are illustrated in the accompanying drawings, in which:

Figure 1 is a front elevation, partly broken away, of a bending machine having the improved mandrel thereon.

Figs. 2, 3 and d are sections on lines 2-2, 3 3 and 4- respectively of Figure l;

- Figs. 5 and 6 are to and side elevations respectively of a rnodi ed form of mandrel;

Figs. 7 and 8 are similar views of a second modification; and p 9 and 10 are similar views of a third modification.

The improved mandrel may be used either in hand work or machine work and is, therefore, not limited to its application or use with any particular apparatus. The bendiiig machine shown in Fig. i may be of any desired type. but in the present in stance comprises a tank 10 holding ,the quenching oil or water, an'upright post 11 which supports at its upper end a cylinder 12, these parts being stationary and a mov able cross head 13. rigidly connected to a piston id in cylinder 12, alsoavertically mova. I

ble platform 15 on which the mandrel-l d is supported. Theplatiorin 15' rests upon coiled compression springs 16 and is adapted to be forced downwardly into'tlie tankfby the action ofthe cross head and against will ments and also prevent spring master plate 20 having. a plurality of depending ears 21 to WhlCh are pivotally se-' cured threaded rods 22 which extend downbeing equal in height in positiom "are supporte wardly through are provided with nuts 24 b means of which the rods may be rigi y supported with their up er ends at any desired distance above t e surface of the. platform, that is, with the master plate .20 curved vto 7 any desired radius of curvature.

. A plurality of radially arranged sup ports *oi brid cs 25 clearly shown in Fig. 3, on the master plate 20, t ese members being substantially rectangular but having downwardly extending spaced parallel legs 25 adapted to receive between them the plate 20. A. clamping screw 26 for. the purpose of securing this member to the plate 20. By loosenin these screws, the members 25 maybe shi ed longitudinally of the plate to any desired osition and, by tightening the screws, secure in such position. The upper edges of the supports 25 are provided with semi-circular grooves 25" to receive the spaced parallel, longitudinally extending rods27, the members 25 and rods 27 therefor lyin' parallel to the plate'20.

' A jacent the ends of the plate 20 are secured members 28 which are similarto the supports 25 in outline and are.adjustably secured .to the late 20 by screws 29 in the samemanner. he members 28 are provided, however, with grooves 28 deeper than the grooves 25" of the member 25 and slots 28" extend, downwardly from these grooves for a considerable distance. The provision of these slots enables the grooves 28' to 'be contracted transversely and for this purposes. bolt 30 is'provided which extends from one end of the member 28 to the other, the tightening of the nut of this bolt serving to 0 amp rods 27 firmly in sition.

After the threaded rods '22 have een adjustedto we the plate 20 its desired cur-. vatur", r s 27 are. aid in grooves25" and 28 0 the supporting members and bolts 30 tightened so that these rods'are firmly held The mandrel is then ready for use. If desired, guides 31 g fclearly illustrated in Fig. 2, may be provided for accurately positionm the .worki (plpon the mandrel, these-gui es being. rigi y supported upon slots 23 in platform 15 and extends through one leg of each member 2 5 members -32 which are adjustably secured to plate 20 by screws 33.

In the operation of the mechanism above described, a heated spring plate is taken from the furnace in its flat condition and placed upon the mandrel inthe positionindi cated at S (Fig. 1). The piston 14 is then the liquid flows freely against and around the hot spring leaf and quickly cools the same.

or water contained in tank 10, whereupon When the work is cooled to the desired temperature, the piston 14 may be raised, al- Iowmg the platform 15 and mandrel to move upwardly, due to the action of the springs 16, andto allow the operator to remove the work from the machine. Y I When submerged, it will be seen that the oil or other quenching liquid has free access to practically all of the surfaces of the work. It can not only contact with the edges but also freely .flow transversely across its upper and lower surfaces, preventing the formation of gas pockets and insuring the uniform and rapid cooling of the metal throughout each and every section.

The form of-master platetillustrated in Figs. 5- and 6 may b ubstituted, if desired, for that illustrated in Fig. 1. In this modi fication a plurality of pins 40' are secured to the master plate 20', these pins being adapted to' support the work on their outer ends and to occupy a radial position for all degrees of curvature of the master plate.

In Figs 7 I and 8 the'master plate 20"l1as supported thereon a chain '51, the links of which are provided with points 52 which serve to support the work, but which permit the free flow of liquid transversely between the body of the'chain and the work. The

links are rather loosely connected so that the plate 20" may be curved as desired. In Figs. 9 and 10 a master plate 20" is illustrated having a'plurality of pins 61 secured thereto, the up r ends of the ins gging ooved to recelve longitudinal are and any suitable means may be employed to secure them in such position.

.v'It will be obvious to one skilled in the art that still other modifications might be designed and that the invention is not limited to any particular. form of superstructure for supporting. the work. It will also be apparent that the invention is susceptible of adaption to handmachines as .well as to power operated machines.

Having thus described my -invention,.what

ese bars restloosely in the grooves rea ers I claim as new and desire to secure by Letters Patent is:

1. A mandrel of the class described comprising, in combination, a flexible plate, and means supported on said plate constituting a superstructure for-supporting an article to be bent, said supporting means comprising a series of substantially radial members of equal length, and longitudinal bars supported on the outer ends of said members and adapted to receive the work.

2. A mandrel of the class described comprising, in combination, a flexible plate, and means supported on said plate constituting a superstructure for supporting an article to be bent, said supporting means including a plurality of rods arranged in parallel spaced relation to the plate, and means for supporting said rods on said plate and adapted to maintain said rods in parallel spaced relationship to the plate for all curvatures which may be imparted to said plate.

3. In a bending and quenching machine,

in combination, a work supporting mandrel comprising a flexible plate and a super,- s tructure supported thereon for supporting the work, said superstructure being constructed and designed to permitthe free flow of liquid transversely between the work and the flexible plate, and a flexible die adapted to cooperate with said mandrel to bend the work and retain the same in place during quenching, said die being constructed and esigned to allow free flow of liquid transversely across the work on the side opposite the mandrel.

4. In a mandrel, a master plate and a superstructure therefor, comprising in combination, a plurality of spaced parallel rods and means for connecting and supporting said rods in spaced parallel relation to the master plate.

- 5. In a mandrel, a flexible master plate and a superstructure for the master plate comprising a work supporting member and means for supporting saidmember on and .in spaced relation to the master plate.

6. llna mandrel, a flexible master plate and a superstructure therefor comprising a work supporting member and means including'a plurality of members normal to the plate or maintaining and connecting said work supporting member in'spaced relation to the plate.

7. In a mandrel, a flexible master plate and a superstructure therefor comprising a work supporting member and means including a plurality of members adapted to be detachably and adjustably secured to the plate for maintaining said work supporting member in spaced relation to the plate.

In testimony whereof I hereunto. affix my signature. J. WALLACE TAYLOR. 

